As surgical knowledge and techniques have progressed, there has been a corresponding trend toward size reduction of surgical incisions and invasive instruments, thus decreasing patient trauma and contributing to rapidity of patient recovery. This has led to the practice of endoscopy including laparoscopic surgical procedures which are characterized by one or more very small incisions or openings as contrasted with the previously conventional large incisions. Since corrective procedures are conducted through very small incisions or other openings, it has become important to provide for multiple techniques/procedures to be performable by a single very small instrument. Examples of such multiple techniques/procedures include fluid flow control such as irrigation, suction and deployment of one or more surgical electrodes.
Recent discoveries of the danger of transmitting deadly diseases such as AIDS have led to heightened awareness of the importance of complete and thorough sterilization. Although it is possible to clean and sterilize suction-irrigation devices both exteriorally and interiorally, the cleaning and sterilization procedures have been time consuming and costly. Accordingly, there has been a need for continuing improvements in suction-irrigation devices that provide the needed multiple capabilities while being easily and quickly cleaned and prepared for re-use.
Multi-element suction-irrigation devices have heretofore been proposed, illustrative of which are those described in U.S. Pat. No. 790,353 granted to E. S. Estlingen on May 23, 1905; U.S. Pat. No. 2,624,364 granted to G. C. Detlefsen on Jan. 6, 1953; U.S. Pat. No. 4,425,113 granted to Arnold C. Bilstad on Jan. 10, 1984; U.S. Pat. No. 4,425,116 granted to Arnold C. Bilstad et al on Jan. 10, 1984; U.S. Pat. No. 4,852,551 granted to Erie A. Opie et al on Aug. 1, 1989; and U.S. Pat. No. 5,195,959 granted to Paul C. Smith on Mar. 23, 1993. Collectively, these patents disclose various forms of squeeze control, multi-passage conduits, disposable inserts, trumpet-type control valves and hinged housings. However, while these patents individually suggest various ones of the foregoing features, they do not singly or in combination teach or suggest a multi-passage suction-irrigation device that includes all of those features while being adapted for equally easy use in either the right or left hand of the user.
In co-pending U.S. patent application Ser. No. 08/312,479 filed Sept. 26, 1994, there is disclosed an improved suction-irrigation device that includes a hinged housing for ease of opening, a contoured interior adapted for receiving a disposable tri-tubular cassette that is discarded after each use, a plurality of improved trumpet type piston-operated plungers in combination with rollers and wedging surfaces to facilitate squeeze control of flow through the cassette tubes, and push/snap on-off cassette connections for connecting tubing to facilitate rapid deployment and re-deployment of the suction-irrigation device. Through the efficacious use of rollers, wedges and springs, improved flow control is achieved while enhancing the feel associated with operation and reducing required finger pressure.
While the proposals of the foregoing co-pending application offer substantial advantages over the prior art, the mechanisms employed have been found to require care in maintaining internal alignment of parts and to be susceptible to malfunction if subject to jarring impact. Accordingly, while such proposals are generally attractive and offer substantial improvements, there has nevertheless been a need for further improvements.